An example of savings box of the above kind, is known from U.S. Pat. No. 4,967,953 issued Nov. 6, 1990 to Sugawara. The savings box comprises a housing composed of six opaque panels. A transparent window is formed in one of the six panels. A partition is disposed in a plane defined by a diagonal of a predetermined one of the four panels adjacent to the panel having the window and by a diagonal of another panel opposite to the predetermined panel and which is parallel to the diagonal of the certain panel. The partition divides the internal space of the housing into first and second, front and rear, spaces or compartments. A light-reflecting or mirror surface is provided on substantially the entire surface of one side of the partition that faces the window. The housing has formed therein a coin slot which communicates with the second, rear compartment.
A coin that has been inserted through the coin slot and received or deposited in the rear compartment is not visible when viewed through the window as the coin is hidden behind the mirror surface and partition. As a result of reflection by the mirror, when the front compartment of the housing is viewed through the window, the housing interior will look like a hollow box, without the mirror and partition. Thus, the deposited coin is not visible, providing the illusion that it is missing.
In the prior savings box, the mirror is disposed on the diagonal so as to be deliberately concealed so that the housing appears entirely hollow and empty.